CVE-2026-88052

Tesseract is an open source OCR engine. In version 5.5.3 and earlier, UNICHARSET::load_via_fgets in src/ccutil/unicharset.cpp trusts the declared unichar count as a loop bound and uses id as an unchecked index into the unichars vector. unichar_insert_backwards_compatible can leave the vector unchanged for an empty, duplicate, or already-encodable representation, causing id to become larger than unichars.size(). Subsequent set_* calls and the write to unichars[id].properties.enabled then write UNICHAR_PROPERTIES beyond the vector during initialization in both the default LSTM and legacy engines, causing heap corruption, a crash, or potentially controlled corruption. No fixed release is available as of this review.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tesseract-ocr/tesseract/commit/2d04d640db2e8c7e3bab2369d599343b5a8b8443	Patch
https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-2hm8-q5c7-c373	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:tesseract-ocr:tesseract_ocr:*:*:*:*:*:*:*:*

History

16 Sep 2026, 16:21

Type	Values Removed	Values Added
References	~~() https://github.com/tesseract-ocr/tesseract/commit/2d04d640db2e8c7e3bab2369d599343b5a8b8443 -~~	() https://github.com/tesseract-ocr/tesseract/commit/2d04d640db2e8c7e3bab2369d599343b5a8b8443 - Patch
References	~~() https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-2hm8-q5c7-c373 -~~	() https://github.com/tesseract-ocr/tesseract/security/advisories/GHSA-2hm8-q5c7-c373 - Exploit, Mitigation, Vendor Advisory
CPE		cpe:2.3:a:tesseract-ocr:tesseract_ocr::::::::
First Time		Tesseract-ocr tesseract Ocr Tesseract-ocr

Information

Published : 2026-09-10 18:18

Updated : 2026-09-16 16:21

NVD link : CVE-2026-88052

Mitre link : CVE-2026-88052

CVE.ORG link : CVE-2026-88052

JSON object : View

Products Affected

tesseract-ocr

tesseract_ocr

CWE

CWE-129

Improper Validation of Array Index

CWE-787

Out-of-bounds Write

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